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The two dimensional XY model at the transition temperature: A high precision Monte Carlo study

Martin Hasenbusch
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Abstract

We study the classical XY (plane rotator) model at the Kosterlitz-Thouless phase transition. We simulate the model using the single cluster algorithm on square lattices of a linear size up to L=2048.We derive the finite size behaviour of the second moment correlation length over the lattice size xi_{2nd}/L at the transition temperature. This new prediction and the analogous one for the helicity modulus are confronted with our Monte Carlo data. This way beta_{KT}=1.1199 is confirmed as inverse transition temperature. Finally we address the puzzle of logarithmic corrections of the magnetic susceptibility chi at the transition temperature.

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Martin Hasenbusch. 2008-03-20. The two dimensional XY model at the transition temperature: A high precision Monte Carlo study. https://doi.org/10.1088/0305-4470%2F38%2F26%2F003

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